diff --git a/README.md b/README.md
index 4deb2a1..35ec0a2 100644
--- a/README.md
+++ b/README.md
@@ -45,12 +45,14 @@ saml_tools.sh
 
 Bash script ``cget.sh`` retrieves and caches HTTP resources on disk. A previously cached resource is retrieved via HTTP Conditional GET [RFC 7232]. If the web server responds with HTTP 200 OK, the resource is cached and written to stdout. If the web server responds with 304 Not Modified, the cached resource is output instead.
 
-To illustrate, define a couple of HTTP resources and a cache:
+To illustrate, define a couple of HTTP resources, a cache, and a log file:
 
 ```Shell
 $ url1=http://md.incommon.org/InCommon/InCommon-metadata-preview.xml
 $ url2=http://md.incommon.org/InCommon/InCommon-metadata-fallback.xml
 $ export CACHE_DIR=/tmp/http_cache
+$ export LOG_FILE=$CACHE_DIR/cget_log.txt
+$ touch $LOG_FILE
 ```
 
 GET the first resource: